The present invention is directed to a set-up control for a box-making machine which slots, scores and folds a box blank into a collapsed-glued box. In particular, the invention is directed to lateral and rotary axis controls for setting up the rotary elements on a slotter shaft or the like in a box-making machine. Such a box-making machine is described in U.S. Pat. No. 3,371,585.
In manufacturing a collapsed-glued box from a box blank, transversely scored box blanks are stacked on a feed table. A reciprocating kicker bar pushes the bottom blank from the stack into a pair of feed rolls. The rolls grip the blank and feed it to a print section. A printing die mounted on a rotating cylinder prints a surface of the blank as it passes through the print section. Pull rolls grip the blank as it passes through the section and feed it to the next print section. The blank is then passed to a slotter-creaser section.
In the slotter-creaser section, a pair of glue tab elements cut away a portion of the blank to form a glue tab. Slotter knife elements slot the blank at predetermined locations and depths for the box flaps. A trim knife element trims the edge of the blank to assure a uniform gap at the box joint. Creaser elements located between juxtaposed slotter elements crease the blank in line with the slots.
Adhesive is applied to the glue tab and the blank is folded thereafter in a folding section. Folding takes place along the crease lines.
The sections of the machine are movable along hardened tracks to permit operator access to the rotary elements during set-up. Typically, the elements are manually set-up by the operator along lateral and rotary axes to ensure that the box blank is cut, slotted and creased at preselected locations on the blank and for preselected depths.
Control of the position of an element along the longitudinal axis of its associated shaft is termed lateral axis control. Control of an element by rotating it with its associated shaft is termed rotary axis control. Slotter knife elements and creaser elements are moved laterally along associated shafts so that the blank is slotted and creased at the preselected locations. In addition, each slotter knife is rotated with its associated shaft to adjust the depth of the slot in the blank.
Previously, each element was displaced laterally or rotationally to a desired position by manually positioning each element. This required the machine to be stopped and the operator to separate and obtain access to the internal components of the machine sections. The rotary elements were then manually displaced to their desired positions without accounting for backlash or coasting time of the control drive.
Various machines for positioning operating elements in web slitting applications are also disclosed in U.S. Pat. Nos. 3,646,418, 3,786,705, 3,886,833 and 3,952,637.
An advantage of the present invention is that the rotary element can be automatically positioned along lateral and rotary axes without having to separate the sections of the machine for purposes of access by the operator.
Another advantage of the invention is that the rotary elements can be set up without exposing the operator to hazards and without having to shut the machine down.
Another advantage of the invention is that the rotary elements can be set up with automatic compensation of backlash and coasting time.
A further advantage of the invention is that it is accurate and reliable.
Other advantages appear hereinafter.